Apparatus for pulverizing ore and the like



e. JOHNSTON. APPARATUS FOR PULVERIZING ORE AND THE LIKE- APPLICATION HLED AUG 15, 1921.

Patented Nov. 8, 1921.

2 SHEETS-SHEET I.

GE'OEGE Ta/ narrow G. JOHNSTON. APPARATUS ron PULVERIZING ORE AND THE LIKE. AL'PL'CATION FILED AUG, I5, I921.

Patented Nov. 8, 1921.

2 SHEETS-SHEET 2.

UNITED ST TES PATENT OFFICE.

GEORGE JOHNSTON, OF MANCHESTER, ENGLAND.

APPLRATUS FOR PULVERIZING ORE AND THE LIKE.

T 0 all whom it may concern Be it known that I, Gnome JOHNSTON, a subject of the King of Great Britain and Ireland, and a resident of Manchester, England, have invented certain new and useful Apparatus for Pulverizing Ore and the like, for which I have filed Brltish patent application No. 32,672, dated July 30, 1920, of which the following is a specification.

The invention has for its object to provide'a type of apparatus for pulverizing ore or the like by direct crushing with the substantial elimination of abrasive action either upon the ore crushed; or upon the surfaces by which it is crushed.

A unit apparatus made according to the invention, comprises a pair of rolls of comv paratively narrow face and of as great hardness of face as maybe. These rolls are carried in headstocks provided with usual overload release gear, and means are pro vided for the accurate adjustment of the pass between them. The rolls are driven at a comparatively high peripheral speed, and the particles of material to be crushed are fed to them at a velocity as nearly as may be equal to that peripheral speed and in such wise that the particles are presented to the rolls successively and as nearly as may be separately-that is to say that each particle is presented with space between it and the toothed divlder bar for breaklng up the adjacent particles. Various means for carrying out these, the two essential features of the invention, may be rovided, but very conveniently the materia is delivered to the rolls through a. narrow slot-like hopper which may have a central partition. The material is caused to flow through the hop per to the rolls (with a velocity substantially that of the rolls surface) and away from the rolls after being crushed, by an induced current o'f air.

A series of these unit pairs of rolls operating upon the material and with the pass of each successive pair adjusted" to break down the .material successively, 'a determinate amount is preferably oprovided,-'each silocessive pair of rollsbein driven at that greater speed determined- "the successive I is crushed to trayel from rollto roll by an induced stream of .air and is finally delivered to a settling chamber or directly to Specification o! Iietters Iatent.

Application filed August 15, 1921.

Patented Nov. 8, 1921.

Serial No. 492,458.

a lixiviation vat by that current. It is delivered from one pair of rolls on to a guiding device, preferably consisting of a series of triangular and slightly oppositely inclined teeth, from which it passes to ducts, from wllilence 1t 1s delivered to the next pair of r0 s.

The rolls are preferably carried in bear- I mg blocks guided in the headstocks, and are for width of pass by cams earned on spindles parallel with and between the axes of the rolls and pressing equally and oppositely upon the bearing blocks. The cams are operated through trains of gearing provided with pointers indicating on suitably enhanced scales, the width of the pass. Detachable means for truing the rolls by grinding may be provided. An apparatus comprising a series of rolls 1s totally inclosed in an alt-tight casing so that not only may the induced stream of air necessary to cause the flow of material to the rolls and from pair to pair be readily maintained, but also so that the discharge of dust from the apparatus may be avoided.

In the accompanying drawing- Figure 1 is a broken end elevation of a crusherunit employing two pairs of rolls.

Fig. 2 is a broken perspective illustrating more or less sheeted material delivered by the crusher rolls.

Fig. 3 is a vertical section showing the driving gear for the rolls and the fan for creating the suction feed draft through the crushers.

The necessary accuracy of adjustment for width'ofpassoffeach pair ofrolls is provided by cams -H"jearried at each side of the 'housi n'g by spindles-J. Qnthe spindles J are spur-wheels gearing with pinions L on a-shaft M extendin from housin to housing; On the shaft externally to the housings, are' disks Nbyjrotation ofwhich adjustmentof the cams -H is brought abou"t The disks bear indications of the adjustment and are locked by fingers ,I servin as point ers to the indications andpressed own upon point of pass. and which rolls are driven by belts P on pulleys I at a surface speed as nearly as may be that of the stream.

From the nip of the rolls A, 13 the material passes to a guiding device V which bears upon its top a series of comparatively narrow triangular teeth IV, alternate ones of which are slightly oppositely inclined. From the guiding device V, the material passes by way of ducts X formed in the casing, to the second pair of rolls C. D thenip of which is narrower and the surface speed of which (driven by pulleys Y) is proportionately greater. From the second pair of rolls the comminuted material passes over a device Z similar to the device V and from thence to the outlets S. from which it is delivered to a settling chamber, or it may be, directly to lixiviating vats, or to similar machines for further treatment.

What I claim is 1. In pulverizing apparatus, a pair of crushing rolls and means arranged adjacent the nip of the rolls for guiding air-propelled material thereto and means for propelling said material and rotating said .rolls at substantially the same speed.

2. In pulverizing apparatus, a pair of crushing rolls and a feed device for delivering material to the nip of the rolls. said device comprising a feed duct having a guide plate extending into the area between the rolls adjacent the nip and channel means for leading material under the influence of an impelling blast past said guide plate to the nip of the rolls.

3. In pulverizing apparatus, a pair of crushing rolls and a feed device for delivering material to the nip of the rolls, said device comprising a feed duct having :a guide plate extending into the area between the rolls and adjacent the nip, and channel means for leading material under the influence of an impelling blast on opposite sides of said guide plate to the nip of the rolls.

4. In pulverizing apparatus, a pair of high speed crushing rolls, and an air-feed duct opening to the nip of the rolls and adjacent the latter for leading material to the rolls and means for propellin said material and rotating saidrolls at su stantiallythe same speed.

. 5. In pulverizing apparatus, a pair of high speed crushing rolls, and an air feed duct comprising a feed guide plate extend 6. In pulverizing apparatus. a pair of high speed crushing rolls, and an abutment against which the partially-crushed and caked material is discharged, said abutment tending to break up the adhesion between the particles of the cake under the influence of its impact.

7. In pulverizing apparatus, a pair of crushing rolls, means for diverting the discharge therefor at an angle to its normal direction of delivery. and an air channel, arranged at an angle to the flow of said diverted material, to which the latter is delivered.

8. In pulverizing apparatus, successive pairs of crushing rolls, means for delivering the partially crushed material from the first pair of rolls to an air channel lying at an angle to the direction of the flow of said discharged material, said channel leading to the Succeeding pair of rolls to feed thereto the partially crushed material with its particles disassociated.

9. In pulverizing apparatus, successive pairs of crushing rolls, means for delivering material from the first pair of rolls to an air channed having a curvilinear course in which adhesion between the particles of the caked material discharged from the first rolls is broken up, said channel leading to the succeeding pair of rolls for the delivery thereto of the partially crushed material with its adhering particles disassociated. I

10. In pulverizing apparatus, successive pairs of crushing rolls, air channel means for delivering to the first pair of rolls the material to be crushed, an air channel bypassing said rolls and leading to the second pair of rolls, and means for delivering the partially crushed material from the first pair of rolls to said channel to insure its delivery to the second pair of rolls.

11. In pulverizing apparatus, successive pairs of crushing rolls, air channel means for delivering to the first. pair of rolls the material to be crushed, an air channel bypassing said rolls and leading to the second pair of rolls,- means for delivering the partially crushed material from the first pair of rolls to said channel to insure its delivery to the second pair of rolls, and means for breaking up the adhesion between the particles of caked or sheeted material delivered from the first pair of rolls, before it is fed to the second pair.

In testimony whereof I have signed my name to this specification.

GEORGE JOHNSTON. 

